Background

The detection of intrinsic brain activity (iBA) could assist clinical assessment for disorder of consciousness (DOC) patients. Previous studies have revealed the altered iBA in thalamocortical, frontoparietal, and default mode network in DOC patients using functional connectivity (FC) analysis. However, due to the assumption of synchronized iBA in FC, these studied may be inadequate for understanding the effect of severe brain injury on the temporal organization of iBA and the relationship between temporal organization and clinical feature in DOC patients. Recently, the time delay estimation (TDE) and probabilistic flow estimation (PFE) were proposed to analyze temporal organization, which could provide propagation structure and propagation probability at whole-brain level.

Methods

We applied voxel-wise TDE and PFE to assess propagation structure and propagation probability for the DOC patients and then applied the connectome-based predictive modeling (CPM) to predict clinical scores for patients based on the ROI-wise TDE and PFE.

Results

We found that: 1) the DOC patients showed abnormal voxel-wise time delay (TD) and probabilistic flow (PF) in the precentral gyrus, precuneus, middle cingulate cortex, and postcentral gyrus, 2) the range of TD value in the patients was shorter than that in the controls, and 3) the ROI-wise TD had a better predictive performance for clinical scores of the patients compared with that based on ROI-wise PF.

Conclusion

Our findings may suggest that the propagation structure of iBA could be used to predict clinical scores in DOC patients.

中文翻译：

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时滞结构使用静息态功能磁共振成像预测意识障碍患者的临床评分

背景

内在大脑活动（iBA）的检测可以帮助意识障碍（DOC）患者的临床评估。之前的研究通过功能连接（FC）分析揭示了 DOC 患者丘脑皮质、额顶叶和默认模式网络中 iBA 的改变。然而，由于FC中iBA同步的假设，这些研究可能不足以理解严重脑损伤对iBA颞组织的影响以及DOC患者颞组织与临床特征之间的关系。最近，提出了时间延迟估计（TDE）和概率流估计（PFE）来分析时间组织，可以提供全脑水平的传播结构和传播概率。

方法

我们应用体素方面的 TDE 和 PFE 来评估 DOC 患者的传播结构和传播概率，然后应用基于连接组的预测模型 (CPM) 根据 ROI 方面的 TDE 和 PFE 来预测患者的临床评分。

结果

我们发现：1）DOC患者在中央前回、楔前叶、中扣带皮层和中央后回表现出异常的体素时间延迟（TD）和概率流（PF），2）患者中TD值的范围比对照组短，3）与基于 ROI 的 PF 相比，基于 ROI 的 TD 对患者临床评分具有更好的预测性能。

结论

我们的研究结果可能表明 iBA 的传播结构可用于预测 DOC 患者的临床评分。